*{
    margin: 0;
    padding: 0;
}
.both{
    width:100%;
    height: 1500px;
}


.title{
    background-color: black;
    width: 100%;
    height: 10%;
    float: left;
}
.title img{
    width: 5%;
    margin-top: 35px;
    margin-left: 40px;
}
.title p{
    float: right;
    font-size: 80px;
    margin-top: 25px;
    color: white;
    margin-right: 30%;
}
.center{
    width: 100%;
    height: 90%;
}
.bottom ul{
    width: 100%;
    height: 150px;
    float: left;
    box-sizing: border-box;
}
.nav>li
{
    list-style: none;
    width: 28%;
    height: 100%;
    float:right;
    font-size: 30px;
    text-align: center;
    line-height: 150px;
    border: 1px solid #000;
    border-left: none;
    box-sizing: border-box;
}
.bottom ul .fourth
{
    width: 16%;
    height: 100%;
    float:left;
    border-left: 1px solid #000;
    box-sizing: border-box;
}
.bottom ul li img{
    margin-bottom: -20px;
}
.bottom p {
    width: 0px;
    height: 0px;
    border-width:15px;
    border-style:solid;
    border-color:white gray gray white;
    opacity: 0.5;
    margin-top: -63px;
    margin-right: 20px;
    float: right;
}

.sub{
    position: relative;
    margin-top: -905px;
}
.sub li{
    height: 150px;
    opacity: 0;
    list-style: none;
    border: 1px solid black;
    border-bottom: none;
}
.nav>li:hover .sub>li{
    opacity: 1;
}
.sum
{
    margin-top: -302px;
}
.sum li
{
    list-style: none;
    border: 1px solid black;
    border-bottom: none;
    opacity: 0;
}
.nav>li:hover .sum>li{
    opacity: 1;
}


